MEMCACHED_POOL(3)

NAME
memcached_pool - libmemcached Documentation

SYNOPSIS

    #include <libmemcachedutil-1.0/pool.h>
        Compile and link with -lmemcachedutil -lmemcached

    typedef struct memcached_pool_st memcached_pool_st

    memcached_pool_st *memcached_pool(const char *option_string, size_t option_string_length)

        Parameters

            •   option_string -- configuration <> string

            •   option_string_length -- length of options_string without any trailing zero byte

        Returns
            allocated and initialized memcached_pool_st instance on success or nullptr on failure

    memcached_st <#_CPPv412memcached_st> *memcached_pool_destroy(memcached_pool_st *pool)

        Parameters
            pool -- initialized memcached_pool_st instance to free

        Returns
            pointer to the 'master' memcached_st <#_CPPv412memcached_st> instance by legacy

    memcached_st <#_CPPv412memcached_st> *memcached_pool_fetch(memcached_pool_st *pool, struct timespec *relative_time, memcached_return_t <#_CPPv418memcached_return_t> *rc)
        Added in version 0.53: Synonym for memcached_pool_pop

        Parameters

            •   pool -- initialized memcached_pool_st instance

            •   relative_time -- time to block thread and wait for a connection to become available when pool size is exceeded, unless nullptr

            •   rc -- out pointer to memcached_return_t <#_CPPv418memcached_return_t>

        Returns
            pointer to an available memcached_st <#_CPPv412memcached_st> instance

    memcached_return_t <#_CPPv418memcached_return_t> memcached_pool_release(memcached_pool_st *pool, memcached_st <#_CPPv412memcached_st> *mmc)
        Added in version 0.53: Synonym for memcached_pool_push.

        Parameters

            •   pool -- initialized memcached_pool_st instance

            •   mmc -- the memcached_st <#_CPPv412memcached_st> instance to return to the pool

        Returns
            memcached_return_t <#_CPPv418memcached_return_t> indicating success

    memcached_return_t <#_CPPv418memcached_return_t> memcached_pool_behavior_set(memcached_pool_st *pool, memcached_behavior_t <#_CPPv420memcached_behavior_t> flag, uint64_t data)

        Parameters

            •   pool -- initialized memcached_pool_st instance

            •   flag -- the behavior <> to change

            •   value -- the value to set for flag

        Returns
            memcached_return_t <#_CPPv418memcached_return_t> indicating success

    memcached_return_t <#_CPPv418memcached_return_t> memcached_pool_behavior_get(memcached_pool_st *pool, memcached_behavior_t <#_CPPv420memcached_behavior_t> flag, uint64_t *value)

        Parameters

            •   pool -- initialized memcached_pool_st instance

            •   flag -- the behavior <> to read

            •   value -- out pointer to receive the set value of flag

        Returns
            memcached_return_t <#_CPPv418memcached_return_t> indicating success

    memcached_pool_st *memcached_pool_create(memcached_st <#_CPPv412memcached_st> *mmc, int initial, int max)
        Deprecated since version 0.46: Use memcached_pool()

    memcached_st <#_CPPv412memcached_st> *memcached_pool_pop(memcached_pool_st *pool, bool block, memcached_return_t <#_CPPv418memcached_return_t> *rc)
        Deprecated since version 0.53: Use memcached_pool_fetch()

    memcached_return_t <#_CPPv418memcached_return_t> memcached_pool_push(memcached_pool_st *pool, memcached_st <#_CPPv412memcached_st> *mmc)
        Deprecated since version 0.53: Use memcached_pool_release()

DESCRIPTION

memcached_pool() is used to create a connection pool of objects you may use to remove the overhead of using memcached_clone for short lived memcached_st <#_CPPv412memcached_st> objects. Please see libmemcached Configuration <> for details on the format of the configuration string.

memcached_pool_destroy() is used to destroy the connection pool created with memcached_pool_create() and release all allocated resources. It will return the pointer to the memcached_st <#_CPPv412memcached_st> structure passed as an argument to memcached_pool_create(), and returns the ownership of the pointer to the caller when created with memcached_pool_create(), otherwise NULL is returned..

memcached_pool_fetch() is used to fetch a connection structure from the connection pool. The relative_time argument specifies if the function should block and wait for a connection structure to be available if we try to exceed the maximum size. You need to specify time in relative time.

memcached_pool_release() is used to return a connection structure back to the pool.

memcached_pool_behavior_get() and memcached_pool_behavior_set() is used to get/set behavior flags on all connections in the pool.

Both memcached_pool_release() and memcached_pool_fetch() are thread safe.

RETURN VALUE

memcached_pool_destroy() returns the pointer (and ownership) to the memcached_st <#_CPPv412memcached_st> structure used to create the pool. If connections are in use it returns NULL.

memcached_pool_pop() returns a pointer to a memcached_st <#_CPPv412memcached_st> structure from the pool (or NULL if an allocation cannot be satisfied).

memcached_pool_release() returns MEMCACHED_SUCCESS <#_CPPv4N18memcached_return_t17MEMCACHED_SUCCESSE> upon success.

memcached_pool_behavior_get() and memcached_pool_behavior_get() return MEMCACHED_SUCCESS <#_CPPv4N18memcached_return_t17MEMCACHED_SUCCESSE> upon success.

memcached_pool_fetch() may return MEMCACHED_TIMEOUT <#_CPPv4N18memcached_return_t17MEMCACHED_TIMEOUTE> if a timeout occurs while waiting for a free memcached_st <#_CPPv412memcached_st> instance, MEMCACHED_NOTFOUND <#_CPPv4N18memcached_return_t18MEMCACHED_NOTFOUNDE> if no memcached_st <#_CPPv412memcached_st> instance was available, respectively.

Note:
        If any method returns MEMCACHED_IN_PROGRESS then a lock on the pool could not be obtained.

        If any of the parameters passed to any of these functions is invalid, MEMCACHED_INVALID_ARGUMENTS <#_CPPv4N18memcached_return_t27MEMCACHED_INVALID_ARGUMENTSE> will be returned.

SEE ALSO

memcached(1) <https://linux.die.net/man/1/memcached> libmemcached(3) <https://linux.die.net/man/3/libmemcached> libmemcached_configuration(3) <https://linux.die.net/man/3/libmemcached_configuration> memcached_strerror(3) <https://linux.die.net/man/3/memcached_strerror>